I would like to know how to add a guest book to my web site. So people that use my service can post a comment that people can see once I approve their comment.
Take a look at the Disqus service, that’s a free system that you can paste into your page with one or two lines of JavaScript in a Markup Item. It allows you to configure your comments exactly how you like, including “all comments must be moderated”, IIRC.
I’ve used Active-scripts Guestbook script which is installed into the cgi-bin on your server. Its quite configurable and quite secure as well.
I notice that their website says its no longer available but it can still be downloaded from various sources. Not sure what happened to Active-scripts as it was a good resource.